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Subject: Re: [PATCH, net-next 2/2] bpf: avoid -Wmaybe-uninitialized warning
To: Arnd Bergmann <arnd@arndb.de>, Alexei Starovoitov <ast@kernel.org>
Cc: Yonghong Song <yhs@fb.com>, "David S. Miller" <davem@davemloft.net>,
        Song Liu <songliubraving@fb.com>, Martin KaFai Lau <kafai@fb.com>,
        Chenbo Feng <fengc@google.com>,
        Jakub Kicinski <jakub.kicinski@netronome.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20180525213331.2115471-1-arnd@arndb.de>
 <20180525213331.2115471-2-arnd@arndb.de>
From: Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <61a96e95-a256-ef40-c25d-e7dbf4c51b02@iogearbox.net>
Date: Mon, 28 May 2018 00:37:03 +0200
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On 05/25/2018 11:33 PM, Arnd Bergmann wrote:
> The stack_map_get_build_id_offset() function is too long for gcc to track
> whether 'work' may or may not be initialized at the end of it, leading
> to a false-positive warning:
> 
> kernel/bpf/stackmap.c: In function 'stack_map_get_build_id_offset':
> kernel/bpf/stackmap.c:334:13: error: 'work' may be used uninitialized in this function [-Werror=maybe-uninitialized]
> 
> This removes the 'in_nmi_ctx' flag and uses the state of that variable
> itself to see if it got initialized.
> 
> Fixes: bae77c5eb5b2 ("bpf: enable stackmap with build_id in nmi context")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Applied to bpf-next, thanks Arnd!